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1.
J Environ Manage ; 317: 115417, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653838

RESUMO

Trichloroethene (TCE) contamination is a critical environmental hazard, and the substrate options for its biostimulated remediation are limited. This study applied an ozonation-and-biostimulation process to remove TCE from groundwater. The substrate used, denoted as Transferred Energy Element (TEE), was composed of natural organic materials and had a low viscosity (2.914 cP). Ten batch experiments were conducted through the application of micro-nano bubbles (MNBs) and substrates (TEE and EOS® [emulsified oil substrate]). MNBs with an average diameter of 157.5-180.8 nm effectively degraded TCE and dichloroethane within 6 min. Biostimulation using the TEE substrate effectively degraded both TCE and vinyl chloride pollutants and reached a steady state after 25 days. The two-stage dechlorination procedure with MNB treatment as the first stage enhanced TCE removal via biostimulation. MNBs reduced the TCE concentration in the first 20 min, but increased the chloride (Cl-) concentration over the following five days (∼80 mg/L). The procedure with biostimulation as the first stage and 20 min ozonation as the second stage reduced the Cl- concentration by ∼10 mg/L. The Cl- concentrations rebounded after day 25 in the EOS environment. X-ray diffraction revealed that the released Na+ from the TEE settled with Cl- as minerals in the soil. The novel two-stage method for TCE removal was found to be more effective than solo MNB treatment or biostimulation.


Assuntos
Água Subterrânea , Ozônio , Tricloroetileno , Poluentes Químicos da Água , Biodegradação Ambiental , Cloretos , Cloro , Poluentes Químicos da Água/análise
2.
J Environ Manage ; 317: 115387, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653843

RESUMO

The leaching risk of heavy metal (HM) in municipal solid waste incineration fly ash (MSWI-FA) leads to a big challenge for FA landfilling. In this work, the HM leaching patterns were identified via 6 highly available indices of FA, in which 160 stabilized FA samples were collected from 4 incineration plants in eastern China and an explainable machine learning approach based on boosting and game analysis was conducted to assess the leaching potentials of 6 HMs (Cr, Cd, Cu, Ni, Pb and Zn). We found that, there remained high exceeding risks of Cd and Pb in stabilized FA. In addition, the S-Cl (soluble chlorine) content was the most influential factor of the leaching behaviors of Cd, Cu, Pb and Zn, more important than pH in regard to Cu, Pb and Zn. We quantified the influence of S-Cl on the HM leaching of Cd, Cu, Pb and Zn, whereby their leaching concentrations would increase by 223.5%, 215.2%, 216.5% and 222.6%, respectively, for every 0.5 mol/L order increase in S-Cl concentration. Finally, a fast determination criterion for the FA landfill was proposed, that is, FA of which S-Cl was less than 0.412 mol/L was acceptable.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cádmio/análise , Carbono , Cloretos/análise , Cinza de Carvão , Incineração , Chumbo/análise , Aprendizado de Máquina , Metais Pesados/análise , Material Particulado , Resíduos Sólidos/análise
3.
Food Chem ; 393: 133293, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653992

RESUMO

In the current study, the physicochemical and emulsifying properties of modified waxy maize starch obtained through a new environmentally friendly method of esterification were evaluated. The starch modification was carried out in NaOH solution with different levels of octanoyl, myristoyl, and stearoyl chlorides. Increasing the fatty acid chlorides concentration led to the degree of substitution increment, while reaction efficiency and yield decreased. Based on fourier transform infrared spectroscopy results, the presence of two new bands of carbonyl (1740-1750 cm-1) and carboxyl (1570 cm-1) groups in the ester bond confirmed the successful starch esterification process. The level of 0.1 mL fatty acid chlorides/g of starch demonstrated the highest emulsifying properties. Upon esterification, the crystalline structure of amylopectin was destroyed, indicating no gelatinization features. Therefore, using the fatty acid chlorides in an alkaline condition could be suggested as a feasible way to modify waxy maize starch toward hydrophobicity increment with desirable properties.


Assuntos
Amilopectina , Zea mays , Amilopectina/química , Cloretos , Esterificação , Ácidos Graxos , Amido/química , Zea mays/química
4.
Sci Total Environ ; 838(Pt 3): 156407, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35660583

RESUMO

In order to mitigate the problems associated with the deposition of biomass ashes, it becomes essential to use these materials efficiently. One solution to the problem is utilization of these wastes in the concrete industry. Due to the massive development of infrastructure, the demand for cement is tremendously rising which results in the surge of cement concrete by 30 billion tonnes every year. Plant-based straw and husk ashes are residual waste containing high amounts of silica, which can also be accommodated as a pozzolanic material in concrete. This study presents a complete review of various husk and straw ashes and their impacts on the fresh and hardened properties of concrete including its preparation, microstructure, workability, compressive strength, splitting tensile strength and flexural strength. Special emphasis has been given to the durability characteristics of concrete focussing on porosity, water penetration, carbonation, acid resistance, sulphate, and chloride attack. The data gathered shows that fineness of ashes provides filler and pore refinement effect and gains additional hydration products, resulting in an improvement of the mechanical and durability properties of concrete. The addition of ashes as supplementary cementitious materials in concrete enhances the mechanical performance up to a certain replacement. The optimum level of replacement for rice husk ash, wheat straw ash, and sugarcane straw ash was observed at 10-20%. While wheat husk ash, groundnut husk ash, rice straw ash, and millet husk ash provide optimum strength gains at 10% replacement of OPC. An increase in the replacement content of mostly ashes has a positive effect on water absorption and resistance to acid, sulphate, and chloride attacks.


Assuntos
Carbono , Oryza , Biomassa , Carbono/química , Cloretos , Materiais de Construção , Sulfatos , Água
5.
Sci Total Environ ; 838(Pt 3): 156377, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35667427

RESUMO

Water quality is a concern in most river basins worldwide due to the widespread release of pollutants which impacts the freshwater ecosystems. Exploring the relationships between drivers and water quality parameters at the regional scale is key in the identification of appropriate actions for the reduction of water pollution. Regional models are the appropriate tool to achieve this, though their development poses relevant challenges because of the complexity and non-linearity of such relationships. Among the available approaches, Machine Learning (ML) is promising because of its capability to detect complex nonlinear relationships and flexibility in the parameterization, which is learned from data. In this work, we developed regional models of water temperature, dissolved oxygen, arsenic, sulfate and chloride concentrations, as well as electrical conductivity, by using two ML algorithms, Random Forest and Deep feed-forward Neural Network, and compared their performances against the standard Linear Regression model. Our results indicate that the two ML algorithms are much more accurate models for such variables than the classical Linear Regression model, with Deep feed-forward Neural Network being the most effective in identifying the reciprocal importance of the drivers and capturing nonlinear relationships between drivers and water quality variables. Our analysis also revealed that the Julian day and year at which the sample was taken surrogate the air temperature in modeling water temperature and dissolved oxygen, with only a slight performance reduction. Arsenic, sulfate, and chloride show more complex behaviors in which geogenic and anthropogenic sources are intertwined. Dilution exerts a role chiefly for arsenic concentration, which suggests a non-uniform, in space, geogenic origin for this variable.


Assuntos
Arsênio , Rios , Cloretos , Ecossistema , Monitoramento Ambiental/métodos , Aprendizado de Máquina , Oxigênio , Sulfatos , Qualidade da Água
6.
ChemistryOpen ; 11(6): e202200080, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35642137

RESUMO

Living cells often contain compartments with high concentration of charged biomolecules. A key question pertinent to the function of biomolecules is how water dynamics are affected by interaction with charged molecules. Here, we study the dynamical behavior of water in an extreme condition, that is, in saturated salt solutions, where nearly all water molecules are located within the first hydration layer of ions. To facilitate disentangling the effects of cations and anions, our study is focused on alkali chloride solutions. Following a multi-nuclear NMR approach enabling direct monitoring of protons and the quadrupolar nuclei 7 Li, 17 O, 23 Na, 35 Cl, 87 Rb and 133 Cs, we investigate how the translational and rotational mobility of water molecules, chloride anion and corresponding cations are affected within the constrained environment of saturated solutions. Our results indicate that water molecules preserve a large level of mobility within saturated alkali chloride solutions that is significantly independent of adjacent ions.


Assuntos
Cloretos , Água , Álcalis , Ânions/química , Cátions/química , Espectroscopia de Ressonância Magnética , Cloreto de Sódio , Cloreto de Sódio na Dieta , Água/química
7.
PLoS One ; 17(6): e0269621, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35704634

RESUMO

OBJECTIVES: Malnutrition, defined according to Nutritional risk screening (NRS 2002), is commonly observed in patients of Myasthenia gravis (MG), a neuromuscular disorder manifested by varied degrees of skeletal muscle weakness. Because biochemical composition of saliva changes in correspondence to alterations in nutritional status, we tested our hypothesis that a certain saliva component(s) might serve as a biomarker(s) for nutrition status of MG, particularly for those MG patients with high risk of malnutrition. MATERIALS AND METHODS: 60 MG patients and 60 subjects belonging to the healthy control group (HCG) were enrolled in this case-control study. The salivary α-amylase (sAA) activity, salivary flow rate (SFR), pH, total protein density (TPD), and the concentrations of chloride and calcium ions in MG group with or without malnutrition were measured before and after citric acid stimulation. Thereafter, the relationship between sAA activity and BMI was determined in MG and HCG. RESULTS: Compared with HCG, more patients with malnutrition, increased TPD and chloride and calcium concentrations but decreased pH value and SFR both before and after acid stimulation, as well as reduced sAA activity, pH and TPD responses to acid stimulation. MG with malnutrition showed decreased sAA activity and TPD responding to acid stimulation compared with those without malnutrition. Compared with normal BMI, sAA activity response to acid stimulation was reduced in low BMI. There was a significant strong positive correlation between the ratio of sAA activity and BMI in MG. CONCLUSIONS: Salivary biochemical characteristics are abnormally altered in MG with malnutrition. Altered sAA activity responding to acid stimulation was associated with malnutrition. CLINICAL RELEVANCE: Decreased sAA activity responding to acid stimulation can reflect malnutrition state and may be one potential screening marker for MG patients with high risk of malnutrition.


Assuntos
Desnutrição , Miastenia Gravis , alfa-Amilases Salivares , Biomarcadores/metabolismo , Cálcio/metabolismo , Estudos de Casos e Controles , Cloretos/metabolismo , Ácido Cítrico/metabolismo , Humanos , Desnutrição/metabolismo , Saliva/metabolismo , alfa-Amilases Salivares/análise
8.
Neonatal Netw ; 41(3): 137-144, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35644364

RESUMO

Maintenance of electrolyte balance in the neonate is a challenge in the context of illness or prematurity. Neonatal providers' approach to fluid management changes and adapts based on the newborn's age, maintenance needs, deficits, and ongoing losses. Understanding the total body water content of the fetus and newborn is foundational to management of electrolyte disturbances. This article reviews common imbalances of sodium and chloride, identifies causes of imbalances, and discusses current evidence-based treatment options.


Assuntos
Sódio , Desequilíbrio Hidroeletrolítico , Cloretos , Humanos , Recém-Nascido , Equilíbrio Hidroeletrolítico , Desequilíbrio Hidroeletrolítico/diagnóstico , Desequilíbrio Hidroeletrolítico/etiologia , Desequilíbrio Hidroeletrolítico/terapia
9.
Water Res ; 220: 118515, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35700645

RESUMO

Chlorine dioxide (ClO2) applications to drinking water are limited by the formation of chlorite (ClO2-) which is regulated in many countries. However, when ClO2 is used as a pre-oxidant, ClO2- can be oxidized by chlorine during subsequent disinfection. In this study, a kinetic model for the reaction of chlorine with ClO2- was developed to predict the fate of ClO2- during chlorine disinfection. The reaction of ClO2- with chlorine was found to be highly pH-dependent with formation of ClO3- and ClO2 in ultrapure water. In presence of dissolved organic matter (DOM), 60-70% of the ClO2- was transformed to ClO3- during chlorination, while the in situ regenerated ClO2 was quickly consumed by reaction with DOM. The remaining 30-40% of the ClO2- first reacted to ClO2 which then formed chlorine from the DOM-ClO2 reaction. Since only part of the ClO2- was transformed to ClO3-, the sum of the molar concentrations of oxychlorine species (ClO2- + ClO3-) decreased during chlorination. By kinetic modelling, the ClO2- concentration after 24 h of chlorination was accurately predicted in synthetic waters but was largely overestimated in natural waters, possibly due to a ClO2- decay enhanced by high concentrations of chloride and in situ formed bromine from bromide. Understanding the chlorine-ClO2- reaction mechanism and the corresponding kinetics allows to potentially apply higher ClO2 doses during the pre-oxidation step, thus improving disinfection byproduct mitigation while keeping ClO2-, and if required, ClO3- below the regulatory limits. In addition, ClO2 was demonstrated to efficiently degrade haloacetonitrile precursors, either when used as pre-oxidant or when regenerated in situ during chlorination.


Assuntos
Compostos Clorados , Desinfetantes , Água Potável , Purificação da Água , 2,5-Dimetoxi-4-Metilanfetamina , Cloretos , Cloro , Desinfecção , Halogenação , Cinética , Oxidantes , Óxidos
10.
Hippocampus ; 32(7): 552-563, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35703084

RESUMO

The ability of endogenous neurosteroids (NSs) with pregnane skeleton modified at positions C-3 and C-5 to modulate the functional activity of inhibitory glycine receptors (GlyR) and ionotropic É£-aminobutyric acid receptors (GABAA R) was estimated. The glycine and GABA-induced chloride current (IGly and IGABA ) were measured in isolated pyramidal neurons of the rat hippocampus and in isolated rat cerebellar Purkinje cells, respectively. Our experiments demonstrated that pregnane NSs affected IGABA and IGly in a different manner. At low concentrations (up to 5 µM), tested pregnane NSs increased or did not change the peak amplitude of the IGABA , but reduced the IGly by decreasing the peak amplitude and/or accelerating desensitization. Namely, allopregnanolone (ALLO), epipregnanolone (EPI), pregnanolone (PA), pregnanolone sulfate (PAS) and 5ß-dihydroprogesterone (5ß-DHP) enhanced the IGABA in Purkinje cells. Dose-response curves plotted in the concentration range from 1 nM to 100 µM were smooth for EPI and 5ß-DHP, but bell-shaped for ALLO, PA and PAS. The peak amplitude of the IGly was reduced by PA, PAS, and 5α- and 5ß-DHP. In contrast, ALLO, ISO and EPI did not modulate it. Dose-response curves for the inhibition of the IGly peak amplitude were smooth for all active compounds. All NSs accelerated desensitization of the IGly . The dose-response relationship for this effect was smooth for ALLO, PA, PAS and 5ß-DHP, but it was U-shaped for EPI, 5α-DHP and ISO. These results, together with our previous results on NSs with androstane skeleton, offer comprehensive overview for understanding the mechanisms of effects of NSs on IGly and IGABA .


Assuntos
Neuroesteroides , Pregnanolona , 5-alfa-Di-Hidroprogesterona/farmacologia , Animais , Cloretos/farmacologia , Glicina/farmacologia , Neurônios/fisiologia , Pregnanos/farmacologia , Pregnanolona/farmacologia , Ratos , Ratos Wistar , Receptores de GABA-A/fisiologia , Ácido gama-Aminobutírico
11.
J Environ Public Health ; 2022: 9336247, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35712041

RESUMO

In Uganda, tap water is always ensured to be potable. However, people are not sure whether tap water is generally safe for drinking without being boiled. Conversely, bottled water consumption is on the increase in Uganda. The main problem lies in the cost of energy for boiling tap water or purchasing bottled water. This study analyzed results of laboratory tests and consumers' perception for comparison of tap and bottled water in Nakawa division, Kampala. Tap water was sampled at four representative locations. At least 16 different brands of bottled water were considered. The top four most consumer-preferred bottled water brands were selected for further analysis. In our study, 28.8%, 6.06%, and 13.64% of the 142 respondents indicated that bottled water had taste, color, and smell, respectively. However, 27.5%, 25.4%, and 34.5% of the respondents agreed that tap water had taste, color, and smell, respectively. Both tap and bottled water met the World Health Organization (WHO) guidelines for pH, total dissolved solids, chloride, copper, sodium, sulfate, and nitrate. However, a tap water sample was found to contain Coliform bacteria. In this line, affected communities need to thoroughly boil the raw tap water to kill the pathogens. All tap water samples yielded iron concentrations above the WHO recommended limit. Student's t-tests showed that tap and bottled water samples were significantly (p<0.05) different with respect to total dissolved solids, pH, chloride, calcium, magnesium, iron, sodium, sulfate, and nitrate. We emphasize the need for routine maintenance of the water distribution system to check for leakages which can be potential source of contaminations.


Assuntos
Água Potável , Cloretos/análise , Água Potável/análise , Humanos , Ferro/análise , Nitratos/análise , Percepção , Sódio/análise , Sulfatos/análise , Uganda , Qualidade da Água , Abastecimento de Água
12.
J Environ Sci (China) ; 117: 119-128, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35725064

RESUMO

Drinking water utilities are interested in upgrading their treatment facilities to enhance micropollutant removal and byproduct control. Pre-oxidation by chlorine dioxide (ClO2) followed by coagulation-flocculation-sedimentation and advanced oxidation processes (AOPs) is one of the promising solutions. However, the chlorite (ClO2-) formed from the ClO2 pre-oxidation stage cannot be removed by the conventional coagulation process using aluminum sulfate. ClO2- negatively affects the post-UV/chlorine process due to its strong radical scavenging effect, and it also enhances the formation of chlorate (ClO3-). In this study, dosing micromolar-level ferrous iron (Fe(II)) into aluminum-based coagulants was proposed to eliminate the ClO2- generated from ClO2 pre-oxidation and benefit the post-UV/chlorine process in radical production and ClO3- reduction. Results showed that the addition of 52.1-µmol/L FeSO4 effectively eliminated the ClO2- generated from the pre-oxidation using 1.0 mg/L (14.8 µmol/L) of ClO2. Reduction of ClO2- increased the degradation rate constant of a model micropollutant (carbamazepine) by 55.0% in the post-UV/chlorine process. The enhanced degradation was verified to be attributed to the increased steady-state concentrations of HO· and ClO· by Fe(II) addition. Moreover, Fe(II) addition also decreased the ClO3- formation by 53.8% in the UV/chlorine process and its impact on the formation of chloro-organic byproducts was rather minor. The findings demonstrated a promising strategy to improve the drinking water quality and safety by adding low-level Fe(II) in coagulation in an advanced drinking water treatment train.


Assuntos
Compostos Clorados , Água Potável , Poluentes Químicos da Água , Purificação da Água , Cloratos , Cloretos , Cloro , Desinfecção/métodos , Compostos Ferrosos , Ferro , Oxirredução , Óxidos , Poluentes Químicos da Água/análise , Purificação da Água/métodos
13.
J Environ Sci (China) ; 117: 276-284, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35725079

RESUMO

Swimming pools adopt chlorination to ensure microbial safety. Giardia has attracted attention in swimming pool water because of its occurrence, pathogenicity, and chlorine resistance. To control Giardia concentrations in pool water and reduce the microbial risk, higher chlorine doses are required during disinfection. Unfortunately, this process produces carcinogenic disinfection byproducts that increase the risk of chemical exposure. Therefore, quantitatively evaluating the comparative microbial vs. chemical exposure risks that stem from chlorination inactivation of Giardia in swimming pool water is an issue that demands attention. We simulated an indoor swimming pool disinfection scenario that followed common real-world disinfection practices. A quantitative microbial risk assessment coupled with a chemical exposure risk assessment was employed to compare the Giardia microbial exposure risk (MER) and the trihalomethane chemical exposure risk (CER) to humans. The results demonstrated a 22% decrease in MER- and CER-induced health exposure risk, from 8.45E-5 at 8:00 to 6.60E-5 at 19:00. Both the MER and CER decreased gradually, dropping to 3.26E-5 and 3.35E-5 at 19:00, respectively. However, the CER exceeded the MER after 18:30 and became the dominant factor affecting the total exposure risk. Past the 18 hr mark, the contribution of trihalomethane CER far exceeded the risk aversion from microbial inactivation, leading to a net increase in total exposure risk despite the declining MER. Swimmers may consider swimming after 19:00, when the total exposure risk is the lowest. Lowering water temperature and/or pH were identified as the most sensitive factors to minimize the overall health exposure risk.


Assuntos
Desinfetantes , Piscinas , Poluentes Químicos da Água , Cloretos , Cloro/análise , Desinfetantes/análise , Desinfetantes/toxicidade , Desinfecção/métodos , Giardia , Halogênios , Humanos , Trialometanos/análise , Água , Poluentes Químicos da Água/análise
14.
Contrast Media Mol Imaging ; 2022: 6742795, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685670

RESUMO

Objectives: To investigate the value of cerebrospinal fluid chloride (CSF-Cl), cerebrospinal fluid glucose (CSF-GS), cerebrospinal fluid microalbumin (CSF-MALB), and cerebrospinal fluid adenosine deaminase (CSF-ADA) in the differential diagnosis of secondary hydrocephalus. Methods: 103 patients with secondary hydrocephalus treated in our hospital from January 2018 to April 2022 were selected. According to different types, it is divided into the hemorrhagic hydrocephalus group and tumor hydrocephalus group. By detecting the levels of inflammatory factors such as CSF-Cl, CSF-GS, CSF-MALB, and CSF-ADA in the two groups, we can analyze the value of these inflammatory factors in the differential diagnosis of secondary hydrocephalus. Results: The level of CSF-MALB in the hemorrhagic hydrocephalus group was significantly higher than that in the tumor hydrocephalus group, and the difference between the two groups was statistically significant (P < 0.05). There was no significant difference in the levels of CSF-Cl, CSF-GS, and CSF-ADA between the two groups (P > 0.05). The area under ROC curve (AUC) of CSF-Cl, CSF-GS, CSF-MALB, and CSF-ADA in the differential diagnosis of secondary hydrocephalus was 0.438, 0.553, 0.750, and 0.542, respectively, sensitivity was 15.1%, 45.3%, 79.2%, and 18.9%, respectively, and specificity was 96.0%, 80.0%, 80.0%, and 94.0%, respectively. Conclusions: The inflammatory reaction of hemorrhagic hydrocephalus was significantly greater than that of tumor hydrocephalus. Moreover, CSF-MALB is closely related to the pathogenesis of hemorrhagic hydrocephalus. At the same time, CSF-MALB can be used as a good index for rapid differential diagnosis of secondary hydrocephalus.


Assuntos
Hidrocefalia , Tuberculose Meníngea , Cloretos , Diagnóstico Diferencial , Glucose , Humanos , Hidrocefalia/diagnóstico , Tuberculose Meníngea/líquido cefalorraquidiano , Tuberculose Meníngea/diagnóstico
16.
Anim Sci J ; 93(1): e13744, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35699686

RESUMO

The widely used porcine artificial insemination procedure involves the use of liquid-stored semen because it is difficult to control the quality of frozen-thawed porcine sperm. Therefore, there is a high demand for porcine semen. The control and enhancement of sperm function are required for the efficient reproduction of pigs. We previously reported that gamma-aminobutyric acid (GABA) enhanced sperm capacitation and acrosome reaction in mice. In this study, we demonstrated the presence of GABAA receptors in porcine sperm acrosome. Furthermore, we investigated the GABA effects on porcine sperm function. We did not detect any marked effect of GABA on sperm motility and tyrosine phosphorylation of sperm proteins. However, GABA promoted acrosome reaction, which was suppressed by a selective GABAA receptor antagonist. GABA binds to GABAA receptors, resulting in chloride ion influx. We found that treatment with 1 µM GABA increased the intracellular concentration of chloride ion in the sperm. In addition, the GABA concentration effective in the acrosome reaction was correlated with the porcine sperm concentration. These results indicate that GABA and its receptors can act as modulators of acrosome reaction. This study is the first to report the effects of GABA on porcine sperm function.


Assuntos
Reação Acrossômica , Motilidade Espermática , Acrossomo/fisiologia , Animais , Cloretos/farmacologia , Masculino , Camundongos , Espermatozoides/fisiologia , Suínos , Ácido gama-Aminobutírico/farmacologia
17.
Carbohydr Polym ; 291: 119663, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698358

RESUMO

Copper fungicides are fungicides have a wide application, but their toxicity to plant growth and the damage they cause to the environment cannot be ignored. As such, the novel, low toxicity biogenic copper fungicide has strong industrial application prospects. Herein, pyridinylcarbonyl chitooligosaccharide ligands (pCOSx) and their copper complexes (pCOSx-Cu) were synthesized. The results showed that a p-π-π conjugated system was formed in pCOSx, resulting in the formation of a slowly dissociated coordination bond between the nitrogen atom of pyridyl and Cu2+ in pCOSx-Cu. The cumulative release rate of Cu2+ is positively correlated with the electron donating ability of pyridyl. Compared with the commercial copper fungicide thiodiazole­copper, pCOSx-Cu exhibited better antifungal activity, lower phytotoxicity and better biocompatibility. This work demonstrated that it was feasible to construct a conjugated system in a chitooligosaccharide copper complex to improve slow-release performance, which laid a foundation for the in-depth study of green copper fungicides. CHEMICAL COMPOUNDS: Chitooligosaccharide (PubChem CID: 3086191); Nicotinoyl chloride hydrochloride (PubChem CID: 88438); Isonicotinoyl chloride hydrochloride (PubChem CID: 12262826); 2-chloronicotinoyl chloride (PubChem CID: 2774541); Trimethylchlorosilane (PubChem CID: 6397); Tetrabutylammonium fluoride (PubChem CID: 2724141); Copper (II) acetate monohydrate (PubChem CID: 165397).


Assuntos
Cobre , Fungicidas Industriais , Antifúngicos/farmacologia , Quitina/farmacologia , Quitosana , Cloretos , Cobre/química , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Oligossacarídeos
18.
Methods Mol Biol ; 2487: 361-375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687247

RESUMO

Halides are substrates and products of a number of biotechnologically important enzymes like dehalogenases, halide methyltransferases, and halogenases. Therefore, the determination of halide concentrations in samples is important. The classical methods based on mercuric thiocyanate are very dangerous, produce hazardous waste, and do not discriminate between chloride, bromide, and iodide. In this chapter, we describe a detailed protocol for the determination of halide concentrations based on the haloperoxidase-catalyzed oxidation of halides. The resulting hypohalous acids are detected using commercially available colorimetric or fluorimetric probes. The biocatalytic nature of the assays allows them to be implemented in one-pot cascade reactions with halide-generating enzymes. Since chloride is ubiquitous in biological systems, we also describe convenient photometric assays for the selective detection of bromide and iodide in the presence of chloride, obviating the need for laborious dialyses to obtain halide-free enzymes and reagents.


Assuntos
Brometos , Iodetos , Cloretos , Halogênios , Diálise Renal
19.
Food Microbiol ; 106: 104035, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35690439

RESUMO

Chicken meat is frequently contaminated with zoonotic bacterial pathogens such as Campylobacter spp and Salmonella spp. These two bacterial genera are commonly linked with cases of human gastrointestinal disease, thus mitigating their presence in the poultry meat supply chain is paramount. Here, the efficacy of two sanitizers, peroxyacetic acid (PAA) and acidified sodium chlorite (ASC), was tested using whole chicken carcasses obtained either prior to the inside/outside wash or the post-immersion spin chill steps of processing. Two concentrations of PAA (100 and 200 ppm) and ASC (450 and 900 ppm) were tested, and both significantly reduced total viable bacteria and Campylobacter counts per carcass. Both sanitizers also reduced the prevalence of Salmonella on whole carcasses from both processing steps. Log reduction of both the total viable and Campylobacter counts were, however, temperature and processing stage dependent. The efficacy of both PAA and ASC were also compared with sodium hypochlorite. No significant difference between the three sanitizers was observed for the reduction of TVC, Campylobacter or Salmonella using carcasses obtained at either processing step. These results demonstrate that PAA or ASC could be implemented as a replacement or used in addition to sodium hypochlorite to effectively reduce bacteria on whole carcasses.


Assuntos
Campylobacter , Ácido Peracético , Animais , Bactérias , Galinhas/microbiologia , Cloretos , Contagem de Colônia Microbiana , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Carne/microbiologia , Ácido Peracético/farmacologia , Salmonella , Hipoclorito de Sódio
20.
Food Microbiol ; 106: 103757, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35690455

RESUMO

In response to the massive use of biocides for controlling Listeria monocytogenes (hereafter Lm) contaminations along the food chain, strains showing biocide tolerance emerged. Here, accessory genomic elements were associated with biocide tolerance through pangenome-wide associations performed on 197 Lm strains from different lineages, ecological, geographical and temporal origins. Mobile elements, including prophage-related loci, the Tn6188_qacH transposon and pLMST6_emrC plasmid, were widespread across lineage I and II food strains and associated with tolerance to benzalkonium-chloride (BC), a quaternary ammonium compound (QAC) widely used in food processing. The pLMST6_emrC was also associated with tolerance to another QAC, the didecyldimethylammonium-chloride, displaying a pleiotropic effect. While no associations were detected for chemically reactive biocides (alcohols and chlorines), genes encoding for cell-surface proteins were associated with BC or polymeric biguanide tolerance. The latter was restricted to lineage I strains from animal and the environment. In conclusion, different genetic markers, with polygenic nature or not, appear to have driven the Lm adaptation to biocide, especially in food strains but also from animal and the environment. These markers could aid to monitor and predict the spread of biocide tolerant Lm genotypes across different ecological niches, finally reducing the risk of such strains in food industrial settings.


Assuntos
Desinfetantes , Listeria monocytogenes , Animais , Compostos de Benzalcônio/farmacologia , Cloretos , Desinfetantes/farmacologia , Farmacorresistência Bacteriana/genética , Ecossistema , Genômica
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